+ $sCallback = isset($_GET['json_callback']) ? $_GET['json_callback'] : '';
+ if ($sCallback && !preg_match('/^[$_\p{L}][$_\p{L}\p{Nd}.[\]]*$/u', $sCallback)) {
+ // Unset, we call javascript_renderData again during exception handling
+ unset($_GET['json_callback']);
+ throw new Exception('Invalid json_callback value', 400);
+ }
+